Architects, civil engineers, toy companies, NASA, bio-medical research companies, and the data storage industry are all recent users of technologies that developed from research in MSE. Most fields in science and engineering are concerned in some way with materials, but only the field of materials science and engineering focuses directly on them.
Permanent hair dye lasts up to eight weeks. A hair dyeing kit. Semi-permanent hair dye cannot be used to lighten hair. Henna can be used to make a semi-permanent hair dye. Semi-permanent hair color lasts about six weeks or up to about 24 shampoos. When dying hair, it's recommended to wear gloves to prevent staining the hands.
While permanent hair dye can lighten your hair up to 2 shades, demi-permanent hair dye is unable to lighten hair at all. The only way to lighten previously colored hair by more than 2 shades is by using lightener. Typically, we recommend applying hair color every 4-6 weeks.